As a method of forming an organic layer configuring an organic electroluminescence device, a vacuum evaporation method, or a coating method using spin coating, an ink jet, or the like is widely used. Among them, the coating method has excellent mass productivity, and has an advantage that process management is facilitated.
The coating method includes a step of applying a solution obtained by dissolving a forming material of an organic thin film in a solvent on an organic thin film which is a base. In this step, when a part of the organic thin film which is the base of the coating is dissolved in the solvent, a layer configuration is not obtained as designed.
For this reason, an attempt has been made to increase solvent resistance by configuring the organic thin film of a cross-linked resin material. In Non-Patent Document 1, such a technology is disclosed. In Non-Patent Document 1, a solution in which a cross-linking resin formed of a diamine derivative and a photopolymerization initiator are dissolved is applied, and then a hole transport layer is formed by allowing the resin to react by light irradiation. Then, on the hole transport layer formed in this way, an organic thin film including a luminescent material is formed by a coating method.
However, when the hole transport layer is formed by using the technology disclosed in Non-Patent Document 1, a sufficient performance as an organic electroluminescence device is not obtained. For example, in Patent Document 1, when an organic layer is formed by polymerizing a polymerizable compound using a technology disclosed in Non-Patent Document 1, there is a problem that drive lifetime is shortened. In order to solve this problem, the technology disclosed in Patent Document 1 includes a hole transport layer which is formed by polymerizing a polymerizable compound, and a hole injection layer which is disposed to be adjacent to the hole transport layer and contains a polymerization reaction initiator.